Production of hydrocarbyl aluminum hydrides

ABSTRACT

Promotion of aluminum hydrocarbyl synthesis by use of powder alloys of aluminum and lithium and aluminum and calcium.

United States Patent 1191 Kondis Dec. 10, 1974 PRODUCTION OF I-IYDROCARBYL 3,100,786 8/1963 Fernald 260/448 A ALUMINUM HYDRIDES 3,104,252 9/1963 Radd et a1. 260/448 A 3,381,024 4/1968 Toyoshima et al. .1 260/448 A Inventor: Thomas J. Kondis, Pltts urgh, Pa. 3,402,190 9/1968 Toyoshima et a1. 260/448 A Assigneez Aluminum p y of America, 3,687,994 8/1972 Kobetz et a1 260/448 A Pittsburgh, Pa. FOREIGN PATENTS OR APPLICATIONS Jan 15 857,680 1/1961 Great Britain 260/448 A 857,681 1/1961 Great Britain 260/448 A [21] Appl. No.: 323,960

Primary Examiner-H. Sneed 52 us. (:1 260/448 A Hatch; John 51 Int. Cl. (3071 5/06 [58] Field of Search 260/448 A [57] 4 ABSTRACT [56] Ref en e Cit d Promotion of aluminum hydrocarbyl synthesis by use UNITED STATES PATENTS of powder alloys of aluminum and lithium and alumi- 3,013,042 12/1961 Blitzer 61 a1. 260/448 A and calclum' 3,050,541 8/1962 Gould 260/448 A 10 Claims, 1 Drawing Figure PRODUCTION or HYDROCARBYL ALUMINUM I HYDRIDFS BACKGROUND OF THE INVENTION olefinic hydrocarbon and hydrogen to obtain an aluminum hydrocarbyl product. US. Pat. No. 3,104,252 teaches use of aluminum base powder alloys containing titanium, hafnium, zirconium, niobium, vanadium uranium and scandium to provide improved reaction rates in the preparation of dialkylaluminum hydrides. While both of these procedures have been useful in aluminum hydrocarbyl production, a competing side reaction, hydrogenation, often wastes raw materials when olefin is present in the reacting medium, and the rate of reaction, in many instances, has not been as high as desired.

SUMMARY OF THE INVENTION After extended investigation, I have found that use of powder alloys, preferably atomized powder, of aluminum with calcium, and aluminum with lithium, as pro.- moters, catalysts or activators in reactions with aluminum hydrocarbyls or olefins and hydrogen not only alleviates this side reaction problem but also substantially increases the efficiency of the hydrocarbylation reacr tion, particularly in the improved reactivity or rate of reaction. I prefer that the aluminum base alloy powder used according to the invention be preliminarily activated, for example, by ball milling powder produced by atomi zing a melt of aluminum and. calcium, or aluminum and lithium, or a melt of an aluminum-calcium alloy or aluminum-lithium alloy. The ball milling may be performed, for example, in a solution of triethylaluminum in an organic solvent such as benzene in an inert atmosphere.

When I refer herein to aluminum base alloys useful according to the invention, I include aluminum base alloys containing at least 98 percent by weight aluminum to which the alloying calcium or lithium has been deliberately added to the aluminum. The alloying elements can be added to the aluminum by any means known to those skilled in the art. Examples of metallurgical means by which the catalytic elements can be added include the following. (1) The elements can be added directly. (2) The elements, alloys, or inorganic salts can beadded to the primary electrolysis cells. (3) Reductive compounds or mixtures of the elements can be added to-the melting fumace. 1

Another way in which the alloying elements can be used is by blending aluminum base alloys containing a higher-than-necessary concentration of the alloying elements with aluminum or aluminum base alloys containing none, or less than a reaction-promoting amount, of the alloying elements.

Aluminum hydrocarbyl compounds which may be reacted and prepared using lithium and calciumcontaining aluminum base powder alloy promoters according to the invention include aluminumalkyl, aryl, aralkyl and alkaryl hydrides and halides which may be represented by the formula wherein R, is a hydrocarbon radical and R and R hydrogen, halogen or a hydrocarbon radical. The hydrocarbon radical can contain from two to 40 carbon atoms and can be alkyl, aryl, alkaryl or aralkyl.

' The calcium and lithium-containing aluminum base alloys used according to my invention are suitable for preparation of organoaluminum compounds-such as the following: I

Diethylalurninum chloride Diethylalurninum bromide Diisobutylaluminum chloride Diisobutylaluminum bromide Dioctylalurninum chloride Dipentadecylaluminum bromide Didocosylaluminum chloride Diphenylaluminum hydride Di-para-tertiarybutylphenyl aluminum hydride Diphenyloctylaluminum hydride Diphenyloctylaluminum chloride Triphenyloctylaluminum Diethylalurninum hydride Diisobutylaluminum Dioctylaluminum hydride Dipentadecylaluminum hydride Didocosylaluminum hydride Ditetracontylaluminum Triethylaluminum Triisobutylalur'ninum Trioctylaluminum Tripentadecylaluminum Tridocosylaluminum Representative starting aluminum carbonyl compounds or olefins useful in reacting with powdered aluminum alloyed with lithium and calcium according to the invention correspond more or less to the organic radical or hydrocarbon portions of the above-recited formula and specific compounds.

The use of the term olefin herein is intended to include hydrocarbons having ethylenic unsaturation such as ethylene, propylene, butadiene and styrene.

The reaction promoted by calcium and lithiumcontaining aluminum base alloys according to the invention, using triethylaluminum (TEA) as representative'of aluminum hydrocarbyls which may be reacted with hydrogen to form the corresponding hydride, may be represented as follows: Y

The diethylaluminum hydride can then bereacted with ethylene to produce triethylaluminum as follows:

acted according to the foregoing hydrocarbyl reactions employing lithium and calcium-containing powder alloys are triethylaltnninum (TEA triisobutylaluminum ium or calcium employed according to the invention include atomized aluminum, granulated aluminum, powdered aluminum, aluminum powder, or any other type of aluminum particles fine enough to be wet milled orv ground, for example, in a ball mill. The particle size is not critical according to the invention. Preferred milling, when the aluminum base alloy is activated by milling, is in the presence of an inert hydrocarbon such as benzene, hexane, mineral spirits or the like.'Time used when milling is employed for activating the aluminum base alloy powder is not'critical according to the invention, although only 'a few seconds are required to impart the desired activity. Nor are the temperature and pressure during the milling critical, ambient temperature and pressure being satisfactory.

Representative particulate aluminum base alloy powder the hydrocarbyl reaction of which is conducted according to the invention has the following representative particle-size breakdown (U.S. Sieve Series).

MESH WEIGHT l 2440 l l .8 -40+l00 26.6 100+200 18.6 200+325 13.6 "325 Generally, the reaction of the aluminum hydrocarbyl or olefin and hydrogen with the calcium or lithiumcontaining aluminum base alloy is conducted at a temcontaining aluminum base alloy, 325 ml triethylaluminum (2.38 moles) and 2,000 psi hydrogen-(about 2.5

moles). As little as about 0.1 percent by weight of the alloying calcium or lithium is eflectiveaccording to the invention.

BRIEF DESCRIPTION OF THE DRAWING I The drawing is a graph plotting'r'eaction time in minutes against hydrogen (H pressure decrease during the reaction (psi) and showing the improved reaction rate, using calcium-containing and lithium-containing aluminum base alloys according to the invention, in terms of pressure drop per unit time, psi/sec (slope) overthat for substantially pure aluminum (base metal, commercial purity) and for high purity aluminum. The value of the slope indicated in the drawing for'each curve was taken from the steepest portion of the curve.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following eiiamples are illustrative of the invention.

EXAMPLE 1 ple, those containing metals shown useful in elemental form by the aforementioned U.S. Pat. No. 3,100,786 in alloys shown in Table I, if no reaction took place within minutes, as indicated by H pressure drop, the testing was discontinued. Otherwise, the reaction was con tinued until measurement of an initial reaction rate. Reaction rate was measured by the H pressure drop per unit time (psi/sec). For the lithium/aluminum alloy in both instances the tabulated value is the average of two runs.

The reaction was conducted in an autoclave at C at a pressure 2,000 psi hydrogen (about 2.5 moles) in the presence of 20g aluminum or aluminum base alloy (0.74 mole) and 325 ml commercial purity triethylaluminum (2.38 moles). The reaction is believed to be as follows:

The atomized powder (20g of Al) was ball milled in 4 ml of triethylaluminum and 146 ml of benzene prior to use in the reaction.

TABLE 1 Alloying Initial Reaction Rate Induction Constituent Concentration (Following Induction) Period psi/sec. min.

Ti 0.2 1.6 1 (less than) Rare Earths 0.005 0.11 47 Mischmetal 0.005 0.08 54 None 99.99 Al Test stopped, no reaction 60 B 0.1 Test stopped, no reaction 60 B 3.0 Test stopped, no reaction 60 Mg 1.0 Test stopped, no reaction 60 Be 1.0 Test stopped, no reaction 60 Zn 1 5.0 Test stopped, no reaction 60 EXAMPLE 2 This example illustrates the advantage of using Al/ Li and Al/Ca powder alloys according to this invention dialkylaluminum hydride from trialkylaluminum according to the equation set out hereinabove.

solved, assuming that only reactions'(2), (3) and (4) occurred. This quantity, as a percentage of the aluminum initially charged to the autoclave, was compared with the aluminum found to be actually dissolved in the over using physical mixtures of A1 with Li a d A1 with ;5, liquid medium, after separation of the unreacted solids.

Ca. Table II records the rate of reaction in synthesizing Any discrepancy between these two figures is thought to be an index to the extent that reaction l occurred. The data are summarized in Table III.

TABLE I" Amount of Initial Rate Dissolved Aluminum Metal or Alloying Induction Hydrogen a c. rom ctua y Alloying Element Period Consumption H Consumed Found Element by Weight min. psi/sec. 7o "/1 Al I8 020 78 56 Ca 0.16 l l 0.33 69 76 Commercial-Purity Aluminum Atomized Powder The reaction occurred under substantially the same conditions as those in Example 1 except that a different lot of TEA was used.

Table II Simple Addition in Alloy Form to Mill Calcium induction Period min. 59 min. Reaction Rate 0.l9 psi/sec. 0.l0 psi/sec. Lithium Induction Period 8 min. 36 min. Reaction Rate 0.79 psi/sec. 0.l l psi/sec.

EXAMPLE 3 20g (0.74 mole) of the aluminum or aluminum base alloys shown in Table Ill hereinbelow were activated by milling in the presence of a benzene solution containing 0.04 mole triethylaluminum per mole aluminum. The

activated slurry was transferred to a l-liter autoclave, to which 475 ml l-octene (2.9 moles) were added. The autoclave was heated to 120 C. After temperature equilibrium had been reached, 2,000 psi hydrogen was pressed in. Gas pressure inside the autoclave was monitored continuously as a function of time. Competing reactions are thought to have consumed hydrogen according to the following schemes,

s m 2 s is GCEHN; 3H2 2A] 8 17)3 4(C H Al 3H 2Al 6(C H AlH,

where C H is l-octene', and C H is octane. Dioctylaluminum hydride present in the reacting mixture reacts with l-octene according to the equation (4) as long as l-octene is present in the system.

Overall rate of reaction was calculated as psi hydrogen consumed per second. The total amount of hydrogen consumed was used to calculate the theoretical amount of aluminum base alloy that should be dis- The data in Table III show promotion by calcium and lithium-containing aluminum base alloys of conversion of l-octene to aluminum hydrocarbyl compounds, with no appreciable loss of l-octene through side reaction by hydrogenation. The data also confirm that such loss of l-octene does, however, occur when prior art-commercial-purity aluminum is used, and in a major proportion when prior art titanium-containing aluminum base alloy is employed.

While the invention has been described in terms of preferred embodiments, the claims appended hereto are intended to encompass all embodiments which fall within the spirit of the invention.

Having thus described my invention and certain pre ferred embodiments thereof, 1 claim:

1. In a process for reacting aluminum with hydrogen and an olefin or aluminum hydrocarbyl compound, the improvement which comprises reacting the hydrogen and the olefin or aluminum hydrocarbyl compound with an aluminum base alloy powder containing at least 98 percent by weight aluminum and 0. 1-2.0 percent by weight lithium, thereby increasing the reactivity of the aluminum.

2. The improvement of claim 1 wherein the reaction is conducted at a temperature of from about 80 C to about 200 C and at a pressure of from about 60 atmospheres to about 350 atmospheres.

3. The improvement of claim 1 wherein the hydrogen LII and the aluminum hydrocarbyl or olefin are present in excess.

wherein R is a hydrocarbon radical and R and R are hydrogen, halogen or a hydrocarbon radical, said hydrocarbon radical containing from two to 40 carbon wherein R is a hydrocarbon radical and R and R are hydrogen, halogen or a hydrocarbon radical, said bydrocarbon radical containing from two to .40 carbon atoms and being alkyl, aryl, alkaryl or aralkyl.

9. In a process for reacting aluminum with hydrogen and an olefin or aluminum hydrocarbyl compound, the improvement which comprises reacting the hydrogen and the olefin or aluminum hydrocarbyl compound with a powder selected from the class consisting of a lithium-aluminum alloy and a calcium-aluminum alloy wherein the amount of lithium or calcium in the alloy is from about 0.1 to about 2 percent by weight of the alloy, thereby increasing the reactivity of the aluminum.

10. The process of claim 9 wherein the aluminum content of said lithium-aluminum or calcium-aluminum alloys is at least 98 percent by weight. 

1. IN A PROCESS FOR REACTING ALUMINUM WITH HYDROGEN AND AN OLEFIN OR ALUMINUM HYDROCARYL COMPOUND, THE IMPROVEMENT WHICH COMPRISES REACTING THE HYDROGEN AND THE OLEFIN OR ALUMINUM HYDROCARBYL COMPOUND WITH AN ALUMINUM BASE ALLOY POWDER CONTAINING AT LEAST 98 PERCENT BY WEIGHT ALUMINUM AND 0.1-2.0 PERCENT BY WEIGHT LITHIUM, THEREBY INCREASING THE REACTIVITY OF THE ALUMINUM.
 2. The improvement of claim 1 wherein the reaction is conducted at a temperature of from about 80* C to about 200* C and at a pressure of from about 60 atmospheres to about 350 atmospheres.
 3. The improvement of claim 1 wherein the hydrogen and the aluminum hydrocarbyl or olefin are present in excess.
 4. The improvement of claim 1 wherein the mole ratio of aluminum base alloy to aluminum hydrocarbyl or olefin is from about 0.1:1 to about 10:1.
 5. The improvement of claim 1 wherein the aluminum base alloy powder is activated by ball milling in the presence of an inert hydrocarbon prior to said reacting.
 6. The improvement of claim 1 wherein the aluminum base alloy powder comprises atomized powder.
 7. The improvement of claim 1 wherein the aluminum hydrocarbyl compound has the formula
 8. The improvement of claim 1 wherein at least one compound selected from the group consisting of an aluminum hydrocarbyl, an aluminum hydrocarbyl hydride and an aluminum hydrocarbyl halide is formed having the formula
 9. In a process for reacting aluminum with hydrogen and an olefin or aluminum hydrocarbyl compound, the improvement which comprises reacting the hydrogen and the olefin or aluminum hydrocarbyl compound with a powder selected from the class consisting of a lithium-aluminum alloy and a calcium-aluminum alloy wherein the amount of lithium or calcium in the alloy is from about 0.1 to about 2 percent by weight of the alloy, thereby increasing the reactivity of the aluminum.
 10. The process of claim 9 wherein the aluminum content of said lithium-aluminum or calcium-aluminum alloys is at least 98 percent by weight. 